


Knifepoint

by zempasuchil



Category: Supernatural
Genre: Blood Magic, Bloodplay, Community: sassy_otp, Knifeplay, M/M, Porn, Robosassy
Language: English
Status: Completed
Published: 2011-08-29
Updated: 2011-08-29
Packaged: 2017-10-24 09:13:23
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,750
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/261632
Author URL: https://archiveofourown.org/users/zempasuchil/pseuds/zempasuchil
Summary: <blockquote class="userstuff">
              <p>early-mid Season 6: Castiel needs a favor from Sam - namely, his blood. Surprisingly, Sam is not that bothered, but then again he's not quite himself these days. RoboSam/Cas</p>
            </blockquote>





	Knifepoint

"Sam," Castiel said.

He had appeared rather suddenly, he supposed, and so Sam (who was sitting on his motel bed, with a sawed-off and cleaning rag in his hand) suddenly pointing a gun at him should have been expected.

"What the fuck, Cas.” Sam scowls. “This how you get your kicks?"

"I need your blood to hide from heaven."

"I'm sorry." Sam sets down the gun and squints at Castiel. "You what?"

"I understand, that is, I am grateful. For what you did. But I need this. Only a little blood, it won't take any time." Castiel takes off his coat.

"Explain." Sam seems open to this. Good.

"I need to cut you, say an incantation, and drink your blood. It's necessary."

"You didn't run this by Dean, did you."

"No."

Sam laughs, then. "Of course not. Why me, again?"

"The combination of angel, human, and demon blood –"

"Cas," Sam says. It's hard for Castiel to see his eyes. "I know about blood drinking. And I know that if you only drink it, the stuff leaves your system in a day, a few days. You have to refuel."

"Yes."

"You were planning on filling up here every time? When were you gonna tell _me_ that?"  
Castiel looks away. "When it was necessary. It has to be willingly given. I can't force you, Sam."

Sam laughs, scoffing, low. "Sure."

"Sam," Cas says, "I wouldn't." He puts his hands on Sam's shoulders in some attempted gesture of assurance, to show that he can be trusted. At the touch, though, Sam's hands shoot up to grab his forearms, keep him there while Sam sets a burning look on him.

"You think you're coercing me into doing this? Or that I'm sucking it up for you, because I'm _nice_?" Sam's lips quirk, as if he's made a joke, but Castiel is unsurprised not to see it. "Think again, Cas. I'm doing this because _I_ want to." He presses the knife, gleaming and pentagram-engraved, into Castiel's hand. "Now cut me."

"Take your shirt off," Castiel says, but Sam's already going for it, overshirt, t-shirt, tossed to the floor, and then he's stretching out long, face-down on the motel bed.

"This had better not scar." Sam's voice is muffled in the pillow.

"I can heal it when I've finished." Castiel sits on the edge of the bed, squints, takes the knife and cuts, shallow and light but slow, the first sigil. Sam's fists are clenched but his breathing is even, if deep. He doesn't say anything. "If the pain is too much, you can sleep."

"Let you knock me out? I'd rather be awake for when you're cutting me up, Cas."

Castiel frowns, even though Sam can't see. "Suit yourself." He cuts the second sigil, and Sam hisses.

=

"I don't understand why you want this," Castiel says, wiping the blade on his dark trousers occasionally. "This sort of thing is... painful, from what I remember of being human."

"Yeah, well," Sam says, hissing barely between his teeth. "It's a sensation. There are a lot of things out there to feel. And this one's strong."

Castiel is uncomfortable talking about Sam's lack of feelings. So he cuts a little deeper, and Sam makes a high, short noise in his throat, and inhales, pressing back against Castiel a little harder.

"How much? How far are you going to go?" Sam asks. He hadn't even, before Castiel started. Castiel doesn't know if he should feel awe at Sam's trust, or fear at how little he seems to care.

"About forty sigils."

"Then you'll need to use my chest, too." It's not a question. Castiel doesn't say anything, just continues to cut.

The blood begins to trickle from the edges, little lines running down towards the groove of Sam's spine. Castiel cuts a circle, a line, a semi-circle, a swoop. Next sigil. More blood trickles, and a rivulet begins to run down the center of Sam's back. Sam is breathing, shallow, then heavy, then shallow again.

"Are you sure you wouldn't rather be asleep?"

"Oh, you're worried _now?_ Or are you just afraid I'm enjoying myself too much?"

Parallel lines. Perpendicular lines. A circle, then, an interrupted circle. The rivulet is running to the base of Sam's spine, starting to pool there. If Castiel is going to write twenty sigils on Sam's back and twenty on his chest, he has a row and a half left to go. The angle is uncomfortable, so he sets the knife on the bedside table.

"Hey!" Sam says. "I didn't say -"

Castiel gets up on the bed to kneel over Sam's back, his knees bracketing Sam's hips. Sam bucks. "Hold still," Castiel says. He leans forward, putting a hand on Sam's shoulder to steady himself so he can grab the knife. His hand nearly slips on the blood, and Sam hisses and bucks again, but Castiel has him pinned to the bed.

Castiel has the knife. "If you don't hold still," he says, leaning back and releasing Sam's shoulder, "I will put you to sleep whether you want me to or not."

"Fine," Sam says. "Just let me. For a second, all right?" The muscles in his back flex, and he arches, and he pulls one of his arms down underneath him to undo his belt and his jeans, and adjust himself. He pulls his arms back up to frame his head, and says, "You can go again."

Castiel does. By the time he finishes the last row, the small pool (that tipped and smeared when Sam moved under him) at the dip in the small of his back is not so small anymore.

He takes a deep breath, and begins the incantation.

The prelude has Sam flexing and straining, but keeping as still as he can. "Jesus, Cas," he says through gritted teeth, and lets out a groan.

When Castiel begins the litany, each sigil he reads lights up as if from within, cracks of red with the red flesh glowing around it. Sam jolts at the first, and Castiel lunges up to grasp his biceps and pin him to the mattress. "Hold... still!" Sam lets a choked-off moan turn into a humorless, stuttering laugh. He grinds into the mattress, and Castiel squeezes his knees around Sam's hips until he's finished.  
He leans back and Sam lies there, breathing hard. Sam's blood is glowing and it smells like iron, or copper, or petrichor - something charged, not the normal smell. The smell of rite.

Castiel moves down and lowers his face to the base of Sam's back, and laps at the small pool of blood until it's gone.

Sam jolts and as soon as Castiel has lifted his head, flips himself over, leans back on his elbows. He's bleeding on the sheets but Castiel doesn't care, and apparently neither does Sam.

"Let's go," Sam says, and Castiel pushes him back.

=

Vertical line, diagonal, concentric circles. Castiel has to slide the knife's tip carefully down from the ridge of Sam's collarbone, to keep the sigils true. He braces himself on the bed with his left elbow, more lightly with his right arm against Sam's chest when he pauses. His face is close to his work. He can smell Sam, and the blood, earthy and animal, the sour sweat of strain, the tarlike stench of the demon taint.

When he moves to the second line, he can see that Sam is staring at him, and at his own chest where Castiel continues to cut, a vertical line, a shorter line, perpendicular. The blood is running, again, a few drips down his sides, a few in the shallow trenches defining his muscles.

"You're slow," Sam says.

"You could have some patience."

Sam seems to be enjoying the view, though, looking down through hooded, squinted eyes to watch Castiel's hands at work, watch the blood well up.

Loop, curve, horizontal line. Circle, tangent. Then to the last line. Castiel sits back over Sam's hips again, wipes his brow. The concentration necessary, the strong heady smell, the efforts to still Sam. At the release of pressure on his chest, Sam squirms, arches his back, moans a little. The zip on his opened jeans rasps against Castiel's slacks. Castiel looks down, and Sam leers.

"You can't tell me this isn't kinky," Sam says.

Castiel continues to breathe heavily. "What?"

"I've done what you're doing." Sam rolls his hips. Castiel pants. "I know exactly how kinky it is. How you get to hold the knife to flesh, and press, and test. The blood is means to an end. My blood."

"Stop," Castiel says. He leans over Sam to place a hand on his shoulder, to pin him, but Sam laughs and his hips are still twisting under Castiel's.

"You're drinking demon blood, Cas. In small doses, but you are. You've got to. To _save the world_ "

"You don't know -"

"I know how good it tastes."

"Hold _still_." Castiel holds the knife close to Sam's abdomen, hovering over his navel. Just one more line left. "I'll put you down."

"I'm pretty sure I can’t consent if I’m unconscious. But sure, Cas, I'll be good." Sam smirks, but he's looking a little pale under his tan.

Castiel finishes, with some difficulty, all the sigils. Before he speaks the words he pins Sam's shoulders to the bed with his hands, his legs with his legs, his hips with his hips. Sam presses against him every way he can, flexing and fighting, biting his lip, until Castiel finishes the incantation.

He moves, slowly, down Sam's chest. He takes a finger, swipes it down the middle, tastes. Sam is staring at him, breathing hard, more still now. Castiel ducks down to where blood is pooled in Sam's navel, petrichor again, tar and rain, and lowers his head.

His chest is pressed against Sam's erection, straining inside his briefs, the tip just visible over the top. Sam groans at the pressure, and Castiel laps up the blood lying there, and Sam swears.

Suddenly Cas has a huge hand on the nape of his neck, on his shoulders, pressing him down. Sam jerks against him, hard and fast, and Castiel doesn't have time to react to this before Sam is coming, shooting hot streaks up Castiel's throat, under his chin, and striping Sam's own stomach.

Sam sighs deeply, but doesn’t take his hand from Castiel’s shoulders. The translucent white begins to mix with the red blood still on Sam's skin. Panting still, Castiel bows his head, and drinks.


End file.
